This invention relates to sorting apparatus for collating sheets into sets and is particularly adapted for use, although not exclusively, with or as part of an office reproduction machine.
Automatic reproducing apparatus, and in particular office copiers, have the capability of producing a plurality of copies of an original document or other information. In many applications for such office copiers, it is desirable to produce collated sets of copies of the original multipaged document. The collation of the individual copies made in such office copiers into sets is achieved with the utilization of a sorter which generally comprises a plurality of bins wherein each bin is designed to collect one set of copies of the original document. A variety of sorters are well known in the art. Most sorters commercially used with office copiers comprises a plurality of tray members which are spaced apart and extend in an array which may be horizontal, as for example, in U.S. Pat. Nos. 3,944,207 and 4,015,841 or vertical as in U.S. Pat. No. 3,977,667. There are also traveling gate sorters as described, for example, in U.S. Pat. No. 3,414,254 in which sheets are conveyed by a sheet transport past the openings of a vertical array of bins and a movable gate or feed throat traverses across the bin openings for deflecting the sheets into the respective bins in turn. Another type of sorter has fixed bins and a deflector or gate associated with each bin and as a sheet transport advances the copy sheets past the bin openings, deflectors are actuated in turn to guide the sheets from the transport into respective bins. In moving bin sorters such as described in U.S. Pat. Nos. 3,788,640 and 4,055,339, the bins themselves are indexed past a fixed throat to facilitate sheet insertion in the sorter. Rotary sorters having bins extending radially outwardly through an axis of rotation are also shown, for example, in U.S. Pat. No. 3,851,872 and in U.S. Pat. No. 4,073,118 wherein a fan-like array of bins is indexed past a fixed feed throat.
It is generally desired to make the sorting apparatus as simple and as compact as possible. Thus, for any given capacity the bin should be preferably be completely filled. However the capacity of the bins is limited by the space required over the stack for insertion of the final sheets in each of the bins. To alleviate this difficulty it is known from various of the above mentioned patents that the bin entrance openings of the respective bins may be selectively increased in size by relatively moving the bin plates to enlarge the opening as a sheet is fed into it.
An additional sheet sorter wherein individual bin plates are arranged in a fan-like array is that described in U.S. Pat. No. 4,398,712 wherein a plurality of movable sheet receiving bins is attached to a quadrant plate for indexing the input ends of the bins past a fixed feed throat to align the bin openings in line with the feed throat for sheet insertion. The bin plates are arranged in a vertically oriented fan-like array and the quadrant plate is rotatable about an axis. U.S. Pat. No. 4,397,461 describes a downhill sorter wherein the input ends are indexed past the sheet entry location by a rotary shifting member, such as a Geneva wheel, which engages individual bin locating rods to transport the input ends of the bins from one side of the feed throat to the feed throat to the other side of the feed throat. The end of the individual bins opposite the input end are each individually pivotally mounted about separate pivot points in the sorting frame. While capable of generally satisfactorily accomplishing the sorting operation, this apparatus suffers from at least two deficiencies. Like all downhill sorters, it is somewhat limited in the range of sizes of copy paper that may be used, inasmuch as small copy paper will tend to go directly to the end of the bin and frequently block the insertion of subsequent sheets into the bin. Furthermore the power requirements to index the multipivot bins is substantial.
An alternative to the downhill stacking arrangement shown in U.S. Pat. No. 4,397,461 is the uphill sorting or stacking arrangement described in U.S. Pat. No. 4,332,377. In this sorter a plurality of trays are mounted to be indexed by a rotary shifting member, such as a Geneva wheel, progressively past a fixed sheet entry position. The input ends of the bins are supported by pins which slidingly move in guiding slots. The remote ends of the bins are freely supported one on the other for relative longitudinal and pivotal movement.